PROBABLE CAUSE OF THE TOXICITY OF THE SO-CALLED 
POISONOUS GREENSAND 1 
By J. W. Kelly 
Chemical Laboratorian, Office of Drug, Poisonous, and Oil Plant Investigations, Bureau 
of Plant Industry, United States Department of Agriculture 
PURPOSE OF THE INVESTIGATION 
In an article by True and Geise 2 the authors mention a poisonous 
variety of greensand located at Courtland, Va. It was found that when 
greensand from this deposit was applied to plants, even in small quan¬ 
tities, the plants were unfavorably affected, while greensand from other 
deposits was beneficial. 
Since the valuable potassium content of this so-called poisonous green¬ 
sand is as high and as easily available as that found in the other deposits, 
it was thought advisable to make a more complete study of this variety 
with a view to discovering its poisonous constituents, and if possible to 
find some means of overcoming the unfavorable feature, thereby render¬ 
ing useful this and other deposits that might show similar properties. 
CHEMICAL ANALYSES OF TOXIC AND NONTOXIC GREENSAND 
For the purpose of comparing the toxic greensand with the nontoxic 
greensands, chemical analyses were made of deposits from Redbank, 
N. J., and Newcastle, Va., in addition to that from Courtland. The 
material used for these analyses was obtained from the same deposits 
as those studied by True and Geise, and the analyses were made with 
great care. The results are given in Table I, 
Table I .—Analyses of greensand from New Jersey and Virginia 
Constituents. 
Courtland, Va. 
Newcastle. 
Va. 
Red Bank, 
N. J. 
Remarks. 
Si 0 2 . 
Per cent. 
60.14 
Per cent. 
39-83 
Per cent. 
56.07 
Analysis made by using 20 per 
SO,.. 
•53 
2.01 
Absent. 
cent hydrochloric acid and 
Ca b . 
1.23 
4.10 
IO.42 
4.62 
digesting. 
MgO. 
1.74 
1.80 
Mn> 0 ,. 
.28 
1.02 
Trace. 
p 2 o $ . 
Trace. 
•54 
•95 
Fe 2 0 3 . 
13.60 
14.08 
12.00 
Fe O .. 
7-56 
4.89 
8.28 
Al„O s . 
8.06 
10.04 
7.02 
Cr 2 O s . 
NiO . 
Strong trace. 
Absent. 
Absent. 
....do . 
...do . 
...do . 
Free sulphur. . 
Present in 
.. .do . 
.. .do . 
Free sulphur removed by suc¬ 
K 2 0 . 
a p p r e c i- 
able quan¬ 
tity. 
4.76 
j. 10 
7-63 
cessive extraction with ether 
and recrystallization. 
NajO . 
•71 
.49 
•47 
1 Accepted for publication July 2 , 1921 . 
3 True, Rodney H., and Geise, Fred W. experiments on the value of greensand as a source 
OFTOTassium FOR plant culture. In Jour. Agr. Research, v. 15, no. 9, p. 483-492. pi- 33 ~ 34 - 1918. 
Journal of Agricultural Research. 
Washington, D. C. 
abm 
(223) 
Vol. XXIII. No. j 
Jan. 20, 1923 
Key No. G-269 
